DESCRIPTONThis is a base class for communication with devices that have a telnet based command-line interface.
Opens a connection to the device. Pass it the address of the device, the
port to connect to, and regex to use to regognise the device's command
prompt, and a regex to use to recognise the prompt.
Returns an object representing this connection.
- Get output of previous command until next prompt, and return it as one string.
- Ensure we're at a prompt line, and send the passed command.